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    FAO/PL:1969/M/17/1

    WHO/FOOD ADD./70.38

    1969 EVALUATIONS OF SOME PESTICIDE RESIDUES IN FOOD

    THE MONOGRAPHS

    Issued jointly by FAO and WHO

    The content of this document is the result of the deliberations of the
    Joint Meeting of the FAO Working Party of Experts and the WHO Expert
    Group on Pesticide Residues, which met in Rome, 8 - 15 December 1969.

    FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

    WORLD HEALTH ORGANIZATION

    Rome, 1970

    FOLPET

    IDENTITY

    Chemical name

    N-(trichloromethylthio)phthalimide

    Synonyms

    Phaltan(R)

    Structural formula

    CHEMICAL STRUCTURE 

    Other relevant chemical properties

    The pure material is a white, crystalline solid, m.p. 117°C. It is
    practically insoluble in water at room temperature and is only
    slightly soluble in organic solvents. The technical product is 90%
    pure. The impurities in the technical product consist of up to 4.5
    percent phthalimide, up to 2.5 percent water, up to 2.5 percent
    calcium carbonate, and less than 1 percent unidentified products. It
    is formulated as 50 percent wettable powder (Ortho Phaltan 50 W); a 75
    percent wettable powder is also formulated. Folpet is stable when dry
    but hydrolyses slowly in water at room temperature, rapidly at high
    temperatures or under alkaline conditions.

    EVALUATION FOR ACCEPTABLE DAILY INTAKE

    BIOCHEMICAL ASPECTS

    The hydrolysis products of folpet (I) are phthalimide (II), chloride
    ions, and various inorganic forms of sulphur. Phthalimide is further
    hydrolysed to phthalic acid (IV) and ammonia. No organochlorine or
    organosulphur products have been detected. In the presence of
    sulfhydryl compounds folpet is degraded extremely rapidly giving the
    same products as from hydrolysis. In blood, the sulphenimide bond of
    folpet is rapidly cleaved with the formation of phthalimide, the half
    life being about one minute. The hydrolysis therefore appears to
    proceed as follows (Dye, 1969):

    CHEMICAL STRUCTURE 

    Because the group attached to the imide nitrogen is the same in folpet
    as it is in captan, it is reasonable to assume that in the presence of
    sulfhydryl groups (e.g. as in cysteine) the trichloromethylthio group
    will break down to give chloride ions by a series of reactions similar
    to those described in the monograph on captan (Owens, 1969).

    Because the trichloromethylthio moiety is the same in both captan and
    folpet, the only difference in the two compounds being that the ring
    portion of folpet is aromatic, it has been assumed that all metabolic
    data for captan relative to the trichloromethylthio portion of the
    molecule will also be applicable to folpet (Dye, 1969) (see the
    monograph on captan).

    Special studies on reproduction

    Rat

    Four groups, each of 8 male and 16 female rats, were fed technical
    folpet (94.4 percent purity) at dietary levels of 0, 100, 500 and 1000
    ppm (active ingredient) in a three-generation study. Parental animals
    were on the test diet for 79 days before mating and continuously
    thereafter. There were no adverse effects on body-weight gain or
    terminal organ-weights of parental animals, or on reproductive
    performance, fertility, lactation, litter-size or incidence of
    stillbirths in any test group. Pup survival at 5 and 21 days, and
    weanling weights in all test groups were comparable with the controls.
    Histopathology performed on parental animals of each generation and on
    F3b weanlings in the 0 and 1000 ppm groups revealed no changes which
    could be correlated with the ingestion of folpet (Kennedy et al.,
    1967a).

    Special studies on teratogenicity

    Chicken-egg

    Folpet was injected in dimethylsulphoxide solution into the yolk or
    air cell of fresh fertile chicken eggs at levels which varied from 3
    to 20 mg/kg egg-weight. The eggs were incubated and non-viable embryos
    and hatched chicks were examined for gross abnormalities. In a total

    of 830 eggs injected with folpet the incidence of malformations was
    8.19 percent. The metabolites of folpet, phthalimide (305 eggs) and
    phthalic acid (290 eggs) were also injected under similar conditions
    using dimethylsulphoxide as a solvent for phthalimide and ethanol for
    phthalic acid. A control group comprising over 1500 eggs was also
    injected with dimethylsulphoxide alone and another group of several
    thousand eggs with ethanol alone. The incidence of malformation was
    3.93 percent for phthalimide, 3.10 percent for phthalic acid and less
    than 2.0 percent for the controls. Micromelia amelia and phocomelia
    accounted for most of the deformities (Varrett et al., 1969).

    Hamster

    Groups of 10 pregnant Syrian Golden hamsters were fed technical folpet
    at dietary levels approximately equivalent to 0, 125, 250, 500 or 1000
    (eight animals only) mg/kg body-weight per day from gestation days 4
    to 15 inclusive. On day 15 of gestation all animals were sacrificed
    and foetal examination was carried out. Maternal body-weight gains
    were decreased over the feeding period in the 250 and 500 mg/kg groups
    while at the highest level there was a weight loss recorded. There was
    an increase in the number of resorption sites at the two highest
    dose-levels compared with the control group. Growth appeared to be
    retarded in the foetuses from all test groups. The mean number of
    foetuses per litter was reduced at the two highest dose-levels. There
    were no gross or skeletal abnormalities attributable to folpet at any
    of the levels used (Arnold et al., 1968).

    A companion study, in which folpet was given by intubation, was
    carried out. Hamsters were given a single dose of 0 (11 pregnant
    females), 125 (9 pregnant females), 250 (5) or 500 (8) mg/kg
    body-weight, half of each group being intubated on day 7 and the
    remainder on day 8. A positive control group was given thalidomide,
    1000 mg/kg body-weight, on day 7. In this experiment the number of
    foetal resorption sites in all groups was higher than normal. The high
    incidence was in the 125 mg/kg group (5.8 per litter) and the low
    incidence was in the 500 mg/kg group (2.5 per litter). The number of
    young per litter was lower in all test groups than in the control.
    There were no gross physical or skeletal anomalies in the test groups
    which could be associated with folpet treatment. No abnormalities were
    found in the group treated with thalidomide (Arnold et al., 1968).

    Monkey

    Groups of from four to six pregnant monkeys (Rhesus and stumptailed
    macque) were given oral doses of 10, 25 and 75 mg/kg body-weight of
    folpet daily on days 21 through 34 of gestation. Thalidomide was given
    as a positive control to groups of 9 or 11 monkeys at levels 5 and 10
    mg/kg body-weight respectively. All foetuses from animals given folpet
    were grossly normal except for one Rhesus foetus each from the 25 and

    75 mg/kg dose-levels which had 13 pairs of ribs. No abortions occurred
    at the 25 and 75 mg/kg levels of folpet but one abortion occurred at
    the 10 mg/kg level in day 54 of gestation. Abortions and foetal
    deformities occurred in the groups given thalidomide (Vondruska,
    1969).

    Rabbit

    Groups of pregnant New Zealand albino rabbits were given folpet at
    dose-levels of 0, 18.75 (5 rabbits), 37.5 (5) or 75 (7) mg/kg
    body-weight on gestation days 6 to 18 inclusive. The dose was
    administered by gelatin capsule. Positive control animals were given
    thalidomide at various dose levels. On day 29 each doe was sacrificed
    and the young removed by Caesarean section. Folpet produced signs of
    toxicity in the dose. At the two higher dose levels there was a loss
    in body-weight over the period of treatment (days 6 to 18). Also at
    these dose-levels the incidence of foetal resorption was higher than
    in the negative control group. There appeared to be a compound-related
    effect on mortality. Examination of 80 embryos from folpet-treated
    rabbits revealed no gross abnormalities; internal structural formation
    was normal and well-defined skeletal development was observed.
    Thalidomide treatment in the positive controls resulted in malformed
    young (Kennedy et al., 1967c; Kennedy et al., 1968).

    Groups of pregnant New Zealand white rabbits were given folpet at dose
    levels of 75 or 150 mg/kg body-weight. Thalidomide was also given to a
    positive control group at the same dose-levels. Thalidomide but not
    folpet produced a teratological response (McLaughlin et al., 1969).

    Rat

    Pregnant female rats of the Charles River strain were given 0, 100 (10
    animals) or 500 (5 animals) mg/kg body-weight of technical folpet by
    oral intubation on days 6 to 15 for the lower dose and days 8 to 10
    for the higher dose-level. Trypan Blue was given by subcutaneous
    injection, 50 mg/kg body-weight, on days 8 to 10 to a fourth group
    serving as a positive control. All rats were sacrificed on the
    twentieth day of gestation. Examination of a total of 169 foetuses
    revealed no significant increase in the incidence of abnormalities in
    the groups given folpet. Internal structural formation was normal, the
    young were present in normal numbers, and were well-formed, Trypan
    Blue treatments produced malformed young as expected (Kennedy et al.,
    1967b).

    A group of 10 pregnant female rats (Charles River and Sprague Dawley
    derived strain) was given oral doses of 100 mg/kg body-weight/day of
    folpet from day 6 to day 15 of gestation and another group of four
    pregnant rats was given oral doses of 500 mg/kg body-weight/day from
    day 8 to day 10. Examination of 120 foetuses in the 100 mg/kg group,

    49 foetuses in the 500 mg/kg group and 200 foetuses from an untreated
    control group gave no evidence of abnormalities related to the
    administration of folpet (Kennedy et al., 1968).

    Studies on the metabolite phthalimide

    Rabbit (teratogenic study)

    Groups of 10 female Dutch Belted Rabbits were given 0 or 75 mg/kg
    body-weight of phthalimide (the hydrolytic metabolite of folpet), via
    gelatin capsule, on day 6 through 16. A treated control group received
    75 mg/kg of thalidomide over the same period. On day 28 the rabbits
    were killed, the young removed by Caesarean section, and examined for
    abnormalities. No adverse effects of phthalimide were noted on the
    parental females or on the 24-hour survival rate of the young. No
    abnormalities, external, internal or skeletal, were seen in the test
    group but were present in the treated controls. Resorption of foetuses
    occurred in three of seven does in the thalidomide group and in one of
    ten in the phthalimide group. This animal lost 220 grams in weight
    between day 11 and 16. Three pups were aborted on day 25, and three
    resorption sites were present which accounted for all the implantation
    sites

    Acute toxicity

                                                                  
                             LD50mg/kg
    Animal    Route          body-weight    References
                                                                  

    Rat       oral           >10,000        Elsea, 1956

    Rabbit    percutaneous   >22,600        Kay and Calandra, 1960
                                                                  

    Short-term studies

    Dog

    Four groups of dogs (three males and three females per group) were
    given folpet at dose-levels of 0, 250, 1000 and 1500 mg/kg
    body-weight. The compound was given orally by capsule 5 days a week
    for 17 months. At 12 months 2-3 dogs (male and female) from each group
    were sacrificed for pathologic study. The remainder were sacrificed
    for pathological study after 17 months. Total mean weight-gain over
    the duration of the test was depressed in both sexes at the highest
    dose-level. None of the animals died during the test. Haematologic
    studies, urinalyses, liver function tests (bromosulphthalein
    retention), serum alkaline phosphatase and blood urea nitrogen
    determinations all showed no unusual findings. There were no gross or
    microscopic pathologic changes which could be correlated with the test
    material (Key and Calandra, 1961a).

    Rat

    Groups each comprising 10 male and 10 female rats were fed dietary
    levels of 0, 0.1, 0.32 and 1 percent of folpet for 12 weeks. Growth
    was normal except in the male rats fed the 1 percent level where there
    was a significant decrease. There were no gross abnormalities.
    Histopathological examination of liver, kidneys, adrenals, intestines,
    lungs and gonads of two male and two female animals of each group
    revealed no abnormalities (Weir, 1956).

    Long-term studies

    Rat

    Folpet was fed to four groups of rats at dietary levels of 0, 0.1,
    0.32 and 1.0 percent for 17 months. Each test group consisted of 30
    males and 30 females, with 60 rats of each sex in the control group.
    After 12 months on the test, 5 males and 5 females of each test group
    (10 of each in the controls), were killed for pathologic study.
    Body-weight data showed a slight adverse effect on growth of rats fed
    1 percent folpet in their diet. An increase in spleen to body-weight
    ratio in this group, observed at 12 months was not present in the rats
    examined after 17 months on the diet. There were no effects on
    mortality, tumour incidence, haematologic studies, urinalysis, gross
    or histopathology that were attributable to the feeding of folpet (Kay
    and Calandra, 1961b).

    COMMENT

    In the two species used in acute toxicity studies, an LD50 value was
    not obtained. The 17-month study on dogs and the 17-month rat study
    indicate a high tolerance, by these species, to chronic exposure to
    this material. These studies should, however, have been of at least
    two-years duration to determine if there may be a potential for
    carcinogenicity. Reproduction and teratogenicity studies on folpet,
    have been carried out on rats, hamsters, and two strains of rabbits.
    No evidence of teratogenic effects has been reported. As there are
    indications of toxic effects on the mothers in the teratogenicity
    studies with hamsters and rabbits, it is recommended that further
    studies be done on these two species. Because of the uncertainty
    regarding embryotoxicity, and since the long-term study in rats was
    only 17 months' duration, a temporary adi is recommended.

    TOXICOLOGICAL EVALUATION

    Level causing no significant toxicological effect

    Rat:  3,200 ppm in diet, equivalent to 160 mg/kg body-weight/day

    Dog:  1,000 mg/kg body-weight/day

    Estimate of temporary acceptable daily intake for man

    0-0.16 mg/kg body-weight

    RESIDUES IN FOOD AND THEIR EVALUATION

    USE PATTERN

    Folpet is a protective fungicide used mainly for foliage application
    at about 0.1 percent active ingredient.

    Pre-harvest treatments

    Rates of application and intervals between treatment and harvest are:

    Citrus fruits               - 0.12 percent active ingredients applied
                                  at 2/3 petal fall, 2 weeks after petal
                                  fall, on full flush growth in August and
                                  September. Use up to harvest.

    Other fruits                - 0.09-0.12 percent active ingredient,
                                  applied as needed at 7-14 day intervals
                                  up to harvest.

    Avocados                    - 0.18 percent active ingredient, applied
                                  as needed at 2 to 3 week intervals up to
                                  harvest.

    Small fruits and berries    - 1.1 to 2.2 kg a.i./ha, applied as needed
                                  at a 7 - 10 day intervals up to harvest.

    Cranberries                 - 5.0 kg a.i./ha, applied as needed at
                                  10-14 day intervals up to 30 days of
                                  harvest.

    Vegetables                  - 1.1 to 4.5 kg a.i./ha, applied as needed
                                  at 7 to 10 day intervals up to harvest.

    Celery                      - Same schedule up to 7 days of harvest.

    Post-harvest treatments

    No post-harvest treatments are recommended.

    Other uses

    Ornamentals - 0.12 percent a.i., applied as needed at 7-10 day
    intervals.

    RESIDUES RESULTING FROM SUPERVISED TRIALS

    The residue data are from treatments made under commercial conditions
    in the U.S.A. (Table I). It is found that the residue patterns of

    folpet follow those of captan. Rain causes a loss of both compounds.
    The development of the wax as the fruit ripens tends to retain the
    residue. Generally the initial level of folpet is reduced by one half
    within a week or two. The residue levels of the fruit pulp and fruit
    juice are found much lower than those of the parent whole fruits.

    TABLE I
                                                                                       
    Residues from field trials (Dye, 1969)

                        Rate of                           Pre-harvest    Folpet
                        application         Number of      interval      residue
    Crop                (kg a.i. per ha)    treatments      (days)       (ppm)
                                                                                   

    Apples              (0.1% to run-off)      1              0-3        2.2-10.5

    Blueberries         2.8 (0.1%)             1-6            0-2        7.0-23.4

    Cherries            (0.1-0.2%)             3-5            0-1        3.7-8.9

    Fresh currants      0.25-0.37              1-5            0-1        8.0-33.0

    Grapes              2.7-3.4 (0.1%)         1-4            0-1        7.6-25.0

    Grapefruits         (0.1-0.2%)             1              0-1        2.4-5.9

    Oranges             (0.1-0.2%)             1              0-1        2.9-8.1

    Raspberries         1.1-2.8 (0.1%)         1-3            0-1        4.6-13.9

    Strawberries        0.3-2.8                1-8            0-1        1.7-5.7

    Cantaloup,
    whole               2.3                    1              0-1        0.6-1.1

    Cucumber            2.3                    1              0-1        0.8-1.9

    Onion, bulb         (0.1%)                 7-8            0-7        0.4-1.2

    Tomatoes            1.0-2.3                1              0-1        1.7-4.1

    Watermelons,
    rind                (0.2%)                                14         0.0-0.3

    pulp                (0.2%)                                14         0.0-0.1
                                                                                   
    
    FATE OF RESIDUES

    General comments

    The remarks under 'BIOCHEMICAL ASPECTS' earlier in this monograph,
    particularly those relating to the hydrolysis of folpet, pertain to
    the behaviour of residues in crops or foods both before and after
    consumption.

    In animals

    In animals folpet is expected to be subject to the similar degradative
    reactions as in plants but no actual data have been available for
    evaluation.

    In plants

    No published data are available from actual studies of the residues in
    plants. It is highly probable however that degradation products of
    hydrolysis as outlined above could be found; but this requires further
    confirmatory studies.

    In soil

    The instability of the compound would not permit build-up in soils.
    However, no experimental data were available for confirmation.

    In storage and processing

    No general quantitative estimates about the effect of washing on the
    folpet residues can be made. It is, however, believed that a
    relatively high portion of residues could be removed. This is
    supported by a single figure on oranges on which washing reduced a
    residue of 8.1 ppm down to 1.1 ppm (Dye, 1969).

    Peeling of fruits is also expected to reduce folpet residues even more
    than washing but lack of data does not allow definite conclusions to
    be drawn.

    In refrigerated storage as well as in frozen products folpet residues
    are expected to be very stable. Any special treatment, e.g. blanching,
    before such storage however may reduce the folpet residues. Data are
    not available for final evaluation. The only figures available
    concerned frozen cherries which contained a folpet residue about 10
    percent of the residue level of unprocessed cherries (Dye, 1969).

    Juice extracted from folpet treated grapes have contained small
    amounts of folpet. The residues in juice in most instances were less
    than 1 ppm although there were few figures up to 5 ppm (Dye, 1969).
    The possible occurrence of folpet in grape juice is of practical
    importance because folpet can cause slight suppression of fermentation
    and produce a poor flavour in wines (Chalkov and Vanev, 1968).

    The canning process is expected to be very destructive to folpet
    residues. The only data available are for canned cherries which were
    found to contain a residue less than the detection limit of the
    analytical method although the unprocessed cherries had residues up to
    5.6 ppm (Dye, 1969).

    METHODS OF RESIDUE ANALYSIS

    A method of residue analysis (Anon., 1960) is based on extraction with
    benzene, clean-up with activated carbon, and reaction with resorcinol
    to give a yellow product which is measured in a colorimeter. This
    method, however, cannot distinguish between folpet and captan, but
    gives the sum of these two compounds. Folpet does not migrate into
    plant tissues; surface stripping is considered adequate for removing
    residues.

    A method is developed to distinguish between folpet and captan (Anon.,
    1961). The sensitivity of the method is not satisfactory.

    Polarographic methods have been set up for determining derivatives of
    folpet and captan (Anon., 1962a; 1962b; Nangniot, 1966).

    Gas chromatographic methods developed for captan (Kilgore et al.,
    1967); Bevenue and Ogata, 1968; Pomerantz and Ross, 1968) and
    detecting residues an low as 0.01 ppm can be used for folpet as well.
    Folpet has been determined with sufficient accuracy at a residue level
    of 2 ppm in red and white wines by an electron capture gas
    chromatographic method (Matta, 1968) using pentane for extraction and
    Florisil for cleanup.

    For regulatory purposes the GLC method has to be further developed.

    NATIONAL TOLERANCES

                           Tolerance
    Country                  (ppm)                  Crop
                                                                        

    Canada                    30          Celery

    Canada                    25          Apples, avocados, blackberries,
                                          blueberries, boysenberries,
                                          cantaloups, cherries, citrus
                                          fruits, cranberries, crabapples,
                                          cucumber, currants, dewberries,
                                          garlic, gooseberries, grapes,
                                          honeydew melons, huckleberries,
                                          leeks, lettuce, loganberries,
                                          muskmelons, onions, pumpkins,
                                          raspberries, shallots,
                                          strawberries, summer squash,
                                          tomatoes, watermelons, winter
                                          squash

    (continued)
                           Tolerance
    Country                  (ppm)                  Crop
                                                                        

    Germany (Fed.Rep.)        15          Fruits, grapes, hops

    Hungary                   10          Fruits, grapes

    Netherlands               20          All crops

    United States of
    America                   50          Celery, cherries, leeks,
                                          lettuce, onions (green),
                                          shallots

    United States of          25          Apples, avocados, blackberries,
    America                               blueberries, boysenberries,
                                          crabapples, cranberries,
                                          currants, dewberries,
                                          gooseberries, grapes,
                                          huckleberries, loganberries,
                                          raspberries, strawberries,
                                          tomatoes

    United States of          15          Cucumbers, garlic, melons,
    America                               onions (dry bulb), pumpkins,
                                          summer squash, winter squash

    United States of          15          Citrus fruits (interim
    America                               tolerance)
                                                                        

    APPRAISAL

    Folpet is used to control fungus diseases on tree fruits, citrus
    fruits, avocadoes, small fruits and berries, vegetables and
    ornamentals. Concentration of the foliage sprays is recommended to
    about 0.1 percent active ingredient. Folpet in nonphytotoxic, though
    some injuries are reported on pears and apples. It in stable when dry,
    but hydrolyses slowly in water at room temperature, rapidly at higher
    temperatures or under alkaline conditions. National tolerances
    established for the residues of folpet in various commodities vary
    from 10 to 50 ppm. Folpet is formulated as 50 percent and 75 percent
    wettable powder.

    The residue data available to the Meeting were from treatments made
    under commercial conditions in the U.S.A. A large variety of crops
    were covered. It is found that the residue patterns of folpet follow
    those of captan. The wash-off effect of rain may be pronounced.
    Generally the initial level of folpet is reduced by one half within a

    week or two. The residue levels of the fruit pulp and fruit juice are
    found much lower than those of the entire parent fruits. The effect of
    processing on the residues may be pronounced.

    The main degradation mechanisms of folpet in plants are postulated to
    be the same as those of captan resulting from the reaction with
    sulfhydryl compounds, mainly phthalimide, to phthalic acid, free
    chlorine ion, and inorganic sulphur compounds. The degradation
    products of folpet in plants are assumed to be the same as in animals.

    The documentation of folpet refers to a colorimetric analysis of
    residues of folpet. The method uses a colour reaction with resorcinol
    and is not specific for folpet. (It reacts with captan, too). For
    differentiating folpet and captan, UV spectrometry can be applied.

    Good agricultural practice was considered to produce residue levels
    determined one day after application as indicated under the following
    headings:

    RECOMMENDATION FOR TOLERANCES, TEMPORARY TOLERANCES OR
    PRACTICAL RESIDUE LIMITS

    TEMPORARY TOLERANCES (effective to 1973)

    Apples                        10 ppm

    Blueberries                   25 ppm

    Cantaloups, whole fruit        2 ppm

    Cherries                      15 ppm

    Citrus fruits                 10 ppm

    Cucumbers                      2 ppm

    Currants, fresh               30 ppm

    Grapes                        25 ppm

    Onions                         2 ppm

    Raspberries                   15 ppm

    Strawberries                   5 ppm

    Tomatoes                       5 ppm

    Water melons                   2 ppm

    Insufficient information was available to enable evaluation of
    residues or tolerances to be suggested for blackberries, cranberries
    and celery.

    FURTHER WORK OR INFORMATION

    REQUIRED (before 30 June 1973)

    1. Long-term studies of sufficient duration to test for possible
       carcinogenic effects.

    2. Additional studies on the effects of the compound on reproductive
       physiology.

    3. Further studies on metabolism, especially on the
       trichloromethylthio-moiety.

    4. Further data on the nature of terminal residues in plants as well
       as on the magnitude of the degradation product: magnitude in 
       relation to the parent compound or toxicological importance.

    5. Further data on the degradation mechanisms of folpet.

    6. Data on the necessary rates and frequencies of application,
       pre-harvest intervals and the resultant residues, from countries 
       other than the U.S.A.

    7. Data on residue levels in raw agricultural products moving in
       commerce.

    8. Qualitative and quantitative data on fate of residues in washing,
       blanching, storing and thermal processing of the treated crops.

    DESIRABLE

    1. Information on the fate of the compound in soil.

    2. Evaluation of the analytical methods by collaborative studies
       taking into account the possible presence of structurally related
       compounds, e.g. captan and captafol.

    REFERENCES

    Anon. (1960) The analysis of residues of captan and folpet. Residue
    method RM-1. Chevron Chemical Co. Unpub. Rept.

    Anon. (1961) The determination of and differentiation between
    residues of Phaltan and captan. Residue method RM-1A. Chevron
    Chemical Co. Unpub. Rept.

    Anon. (1962a) Centre de recherches de phytopharmacie à Gembloux
    (Belgique) Résultats inédits

    Anon. (1962b) Institut agronomique de l'etat (Gembloux-Belgique).
    Résultats inédits

    Arnold, D., Kodras, R. and Fancher, O.E. (1968) Teratogenicity study 
    on Phaltan Golden Syrian hamsters Unpub. Rept. of Industrial
    Bio-Test Laboratories, submitted by Chevron Chemical Co.

    Bevenue, A., and Ogata, J.N. (1968) The examination of mixtures of 
    captan and Phaltan by gas chromatography. J. Chromatog. 36:529-31

    Chalkov, I. and Vanev, S. (1968) Determination of the effect of some 
    new fungicides, used to control gray rot in grapes under field
    conditions, on the enzymic activity of yeasts. Lozarstvo Vinar
    (Sofia) 17:33-40 (Chem. Abstr. 69:34 908 s, 1968)

    Dye, D.F. (1969) Folpet. Unpub. Summary Rept. submitted to FAO and 
    WHO by Chevron Chemical Co.

    Elsea, J.R. (1956) Phthalimide captan analog. Acute oral
    administration. Unpub. Rept. of Hazleton Laboratories submitted by
    Chevron Chemical Co.

    Kay, J.H. and Calandra, J.C. (1960) Acute percutaneous and eye
    irritation studies on Phaltan. Unpub. Rept. of Industrial Bio-Test
    Laboratories submitted by Chevron Chemical Co.

    Kay, J.H. and Calandra, J.C. (1961a) Chronic oral toxicity of
    Phaltan. Pure bread beagle dogs, (with addendum report. Pathological
    findings). Unpub. Rept. of Industrial Bio-Test Laboratories
    submitted by Chevron Chemical Co.

    Kay, J.H. and Calandra, J.C. (1961b) Chronic oral toxicity of
    Phaltan. Albino rats. Unpub. Rept. of Industrial Bio-Test
    Laboratories submitted by Chevron Chemical Co.

    Kennedy, G., Fancher, O.E. and Calandra J.C. (1967a) Three generation
    reproduction study in albino rats-Phaltan. Final Rept. Unpub.
    Rept. of Industrial Bio-Test Laboratories submitted by Chevron
    Chemical Co.

    Kennedy, G., Fancher, O.E. and Calandra, J.C. (1967b) Rat 
    teratogenicity study. Captan, Difolatan and Phaltan. Unpub. Rept. 
    of Industrial Bio-Test Laboratories submitted by Chevron Chemical Co.

    Kennedy, G., Jackson, G., Fancher, O.E. and Calandra, J.C. (1967c) 
    Rabbit teratogenicity study. Captan and Phaltan. Unpub. Rept. of
    Industrial Bio-Test Laboratories submitted by Chevron Chemical Co.

    Kennedy, G., Fancher, O.E. and Calandra, J.C. (1968) An investigation
    of the teratogenic potential of captan, folpet and Difolatan. Toxicol.
    appl. Pharmacol. 13:42-430

    Kilgore, W.W., Winterlin, W. and White, R. (1967) Gas chromatographic
    determinations of captan residues. J. Agr. Food Chem. 15:1035-37

    Matta, M. (1968) Gas chromatographic determination of chlorinated 
    pesticide residues in wine. Vini Ital. 10:171-4 (Chem. Abstr. 
    69:66469 r, 1968)

    McLaughlin, J., Jr., Reynaldo, E.F., Lamar, J.K. and Marliac, J.P.
    (1969) Teratology studies in rabbits with captan, folpet and
    Thalidomide. Toxicol. appl. Pharmacol. 14:641

    Nangniot, P. (1966) L'application des méthodes électrochimiques à 
    l'étude des résidus de pesticides. Meded Rijksfac. Landbouwwetensch.
    31:447-73

    Owens, R. G. (1969) Metabolism of fungicides and related compounds.
    Ann. N.Y. Acad. Sci. 100:144-52

    Palazzolo, R., Fancher, O.E. and Calandra, J.C. (1966) Rabbit 
    reproduction study. Phthalimide. Unpub. Rept. of Industrial Bio-Test
    Laboratories submitted by Chevron Chemical Co.

    Pomerantz, I.H. and Rose, R. (1968) Captan and structurally related
    compounds: thin-layer and gas-liquid chromatography. J. Assoc.
    Offic. Anal. Chem. 51:1058-62

    Varrett, M.J., Mutchler, M.K., Scott, W.F., Reynaldo, E.F. and
    McLaughlin, J. (1969) Teratogenic effects of captan and related
    compounds in the developing chick embryo. Ann. N.Y. Acad. Sci.
    160:334-43

    Vondruska, J.F. (1969) Teratologic investigation of Phaltan in
    Macaca mulatta (Rhesus monkey) and Macaca arctoides
    (stumptailed macque).
    Unpub. Rept. of Industrial Bio-Test Laboratories submitted by
    Chevron Chemical Co.

    Weir, R.J. (1956) N-trichloromethylthiophthalimide, recrystallized
    phthalimide, (phthalimide analog of captan). Subacute
    feeding-rats. Supplement to report dated 23 July, 1956. Unpub.
    Rept. submitted by Hazleton Laboratories to California Spray -
    Chemical Co.
    


    See Also:
       Toxicological Abbreviations
       Folpet (HSG 72, 1992)
       Folpet (ICSC)
       Folpet (WHO Pesticide Residues Series 3)
       Folpet (WHO Pesticide Residues Series 4)
       Folpet (Pesticide residues in food: 1984 evaluations)
       Folpet (Pesticide residues in food: 1986 evaluations Part II Toxicology)
       Folpet (Pesticide residues in food: 1990 evaluations Toxicology)
       Folpet (Pesticide residues in food: 1995 evaluations Part II Toxicological & Environmental)